Waste water is pervasive in our environment and can be generated by diverse sources ranging from stormwater or runoff water which carries surface contaminants such as petroleum hydrocarbons, metals, particulate matter and bacteria directly to natural or man-made impoundments to the more severe discharges of water contaminated with chemical and radioactive waste. Industrial complexes and municipalities must treat relatively large volumes of waste water on a regular basis. In many cases, industrial complexes, factories and municipalities must build permanent water treatment systems for their waste water. In many cases waste water accumulates in man-made impoundments such as underground electrical vaults, secondary containment vaults for underground storage tanks, equipment vaults, sumps, catch basins and storm water retention ponds. As our environment becomes more contaminated, regulatory agencies are imposing restrictions and establishing regulations that preclude discharging anything but minimally contaminated waste water directly into the environment. Options are limited for facilities that do not have an on-site water treatment system and these facilities must either make arrangements to have contaminated waste water transported to an appropriate treatment facility or make arrangements for highly restricted discharge to a sanitary sewer system. Municipal waste water treatment facilities have strict rules with respect to the types of waste water that is allowed into the sewers and as contaminant levels increase, rules are becoming more stringent. Alternative treatment sites are available in some cases but transportation and treatment costs can be significant. There are situations where some waste water streams cannot be discharged into a sewer system or discharged directly to the environment because of environmental regulations or appearances. In many of these situations the contamination is so minimal that transportation to a hazardous waste treatment and disposal site is impractical.
In many situations industrial waste water is generated during construction activities and in most cases that contamination, generally in the form of sediments and small debris, is relatively minimal. There are many approaches to the control of contaminated water generated at construction sites and these approaches range from man-made impoundments to filter socks used to provide crude removal of coarse sediments. However, much of the contaminants generated at construction sites migrate off-site via construction vehicles entering and exiting the site as well as windblown fine particulate matter that mixes with surface water. This contamination that has migrated off site finds its way into below ground structures such as utility and containment vaults.
Filter socks used at construction sites are generally fabricated out of a heavy duty porous fabric with a large apparent opening size which allows mud and rock particles to be discharged into the environment. Conventional filter socks are not suitable for removing fine particles from waste water.
Filter socks do not reliably remove substantial contaminant concentrations. For this reason, it would be desirable to implement a technology that provides the ability to treat waste water contaminated with particulate matter and other prevalent contaminants such as hydrocarbons in an efficient manner that allows the discharge of that treated waste water directly into the environment. Underground electrical vaults and other man-made areas where water accumulates are prone to collecting particulate matter, contaminated water, and other liquids. The current methods employed to address this waste water is to remove that water from any given location with a vacuum truck or other type of pumping and containment vessel and to transport that water off-site for treatment and disposal or, the more complicated process of bringing portable waste water treatment equipment to the site to treat the water. It would be particularly desirable to provide a method capable of providing filtration of waste water for the removal of fine particulate matter, contamination, and associated discoloration so that the water can be discharged directly to the environment with little or no aesthetic or environmental impact.
Disclosed herein is a filter sleeve that can be configured to remove fine particulate matter as well as a range of other contaminants, including but not limited to, hydrocarbons from waste water, so that after filtering, the waste water can be discharged directly to the environment, or made acceptable for discharge into a sanitary sewer system. Current technologies that are employed to address many waste water issues are either relatively ineffective or prohibitively expensive. The filter sleeve can provide filtered removal of sub-micron particulates and it can be configured to remove a spectrum of contaminants, including but not limited to, hydrocarbons and metals from waste water and it can perform these tasks far more efficiently and at considerably lower cost than most current practices.
In one exemplary embodiment, the multi-layer filter sleeve is fabricated from media selected to preferentially remove certain contaminants. For example, in one exemplary embodiment, one layer of the filter sleeve removes particulates larger than 1 micron in size. A second layer removes hydrocarbons and a third layer is in itself composed of a multi-layered composite of porous, granular and reactive media. Adjacent edges of the filtration media can be sewn, sealed, or otherwise bonded together to create a cylindrical structure with openings on each end. In an alternative embodiment the bottom end of the cylinder is closed or sewn shut as well, particularly in those applications where bottom sealing might otherwise be a problem if the cylinder were to be left open. Combination options are relatively unlimited in that filter media can be employed for the removal of a specific particle size and yet another layer, or layers with a different media, can be employed to remove a specific contaminant or contaminants. In other embodiments a plurality of media in layers will be included, since the order and configuration of those layers and media will be chosen as required to remove specific contaminants and particulate sizes.
One or more layers can be implemented in the construction of the filter sleeve and these layers can be composed of diverse filter media in the form of, but not limited to, woven fabric, non-woven fabric, screen cloth, felted material and other media as may be necessary to meet the target filtration requirements.
In some embodiments, the filter sleeve will be implemented by placing the filter sleeve as a cover over the exterior of a porous supporting structure with the lower portion of the filter sleeve weighted to create a seal at the lower extreme of the supporting structure at the point where the supporting structure interfaces with a base surface. The upper open-ended weighted portion of the filter sleeve in this embodiment would be folded inward over the upper edge of the porous supporting structure to provide support for the filter sleeve on the supporting structure.
In some embodiments, the filter sleeve will be implemented by placing the filter sleeve as a liner in the interior of a porous supporting structure with the lower portion of the filter sleeve weighted to create a seal at the lower inner extreme of the supporting structure at the point where the supporting structure interfaces with a base surface. The upper open-ended weighted portion of the filter sleeve in this embodiment would be folded outward over the upper edge of the porous supporting structure to provide support for the filter sleeve on the supporting structure.
In some embodiments, the filter sleeve will be implemented by placing the filter sleeve as a cover over the exterior of a porous supporting structure with the lower portion of the filter sleeve clamped, tied, or otherwise fastened to create a seal at the lower extreme of the supporting structure at the point where the supporting structure interfaces with a base surface. The upper open-ended weighted portion of the filter sleeve in this embodiment would be clamped, tied, or otherwise fastened at the upper edge of the porous supporting structure to provide support for the filter sleeve on the supporting structure.
In some embodiments, a porous structural support will be included in the interior of, or on the exterior of, the filter sleeve to provide such structural support as proves necessary for any given application.
In another embodiment one end of the filter sleeve can be capped or sealed closed so as to create a pouch covering the exterior, or a pouch lining the interior of the supporting structure.
An exemplary implementation of a multi-layer filter sleeve is for the removal of particulate matter and hydrocarbons from water pumped from underground equipment vaults. Equipment vaults are common in many buildings and along thoroughfares where utilities are plumbed sub-surface. Water that collects in these vaults or chambers from groundwater intrusion or other sources may be contaminated with hydrocarbons of varying types and concentrations depending upon the use for any given vault or chamber. The implementation of a filter sleeve configured to remove hydrocarbons provides the ability to discharge water from these vaults or chambers directly into the environment.
While the apparatus and method has or will be described for the sake of grammatical fluidity with functional explanations, it is to be expressly understood that the claims, unless expressly formulated under 35 USC 112, are not to be construed as necessarily limited in any way by the construction of “means” or “steps” limitations, but are to be accorded the full scope of the meaning and equivalents of the definition provided by the claims under the judicial doctrine of equivalents, and in the case where the claims are expressly formulated under 35 USC 112 are to be accorded full statutory equivalents under 35 USC 112. The illustrated embodiments of the invention can be better visualized by turning now to the following drawings wherein like elements are referenced by like numerals.
The invention and its various embodiments can now be better understood by turning to the following detailed description of the preferred embodiments which are presented as illustrated examples of the invention defined in the claims. It is expressly understood that the invention as defined by the claims may be broader than the illustrated embodiments described below.